The Neuroanatomy Core will perform immunohistochemical, in situ hybridization, electron microscopic and computerized image analysis studies to define the organization of selected cellular classes in specific brain regions and determine how they are affected by perinatal nutritional manipulations in collaboration with individual research projects in the program. Qualitative neuroanatomical analyses will include the definition of the spatial distribution, cellular morphology and the localization of relevant molecules in selected cell classes. Quantitative analyses will include measurements of cell size, volume, axonal and dendritic branching patterns and the computation of cell density and unbiased cell counts. These procedures will be accomplished using computer-assisted image analysis, the capture of high-resolution digital images and confocal microscopy. These data will be stored in a relational Access database for the use of all investigators. The specific aims of the neuroanatomy core are: 1) to facilitate the accomplishment of the scientific aims delineated in all of the individual projects of the program by providing expertise in quantitative structural techniques and other technical support as needed. Genotyping of transgenic mice will be performed as required for all investigators. A relational database of anatomical results has been established and will be maintained for correlational studies. Anatomical studies have been prioritized to concentrate on the most scientifically important topics in each project. These comprise the other 2 aims of the core which are to determine the structure correlates of the observed effects of prenatal choline availability on rodent behavior and brain biochemistry and electrophysiology and to define the anatomical and neuropathological features of transgenic mice used in the program project. Preliminary studies strongly suggest that the hippocampus or its connections is a major locus of interest. The core will work with Project 0001 to determine the anatomical distribution of biochemical markers of plasticity and diet-related changes in gene expression defined by expression profiling during development and aging;with Project 0004 to quantify how prenatal availability of choline influences adult neurogenesis and survival;and with Project 0005 to examine selected markers in adult and aging brain that show diet-related alterations during fetal development. The anatomical and neuropathological features of transgenic mice strains used in the program project will be studied. CNS anatomy and pathology affecting many of these strains and the consequences of dietary manipulation have not been previously characterized.